The War in the Clouds 



A battle in the air. An allied monoplane (on the left) rising to attack a German biplane 

 among the clouds over the war front in France. The photograph was taken in mid-air 

 by a third aeroplane, and shows clearly the trenches over which the machines are battling 



An Austrian pilot balloon being inflated from a gas cylinder. These small pilot balloons 

 arc Fcnt aloft just before a Zeppelin foray in order to determine the direction and velocity 

 of the air currents. In time of peace they are employed to obtain temperature read- 

 ings of the upper air for the use of meteorologists 



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